Charm Physics Confronts High-$p_T$ Lepton Tails

Abstract

We present a systematic survey of possible short-distance new-physics effects in (semi)leptonic charged- and neutral-current charmed meson decays. Using the Standard Model Effective Field Theory (SMEFT) to analyze the most relevant experimental data at low and high energies, we demonstrate a striking complementarity between charm decays and high invariant mass lepton tails at the LHC. Interestingly enough, high-$p_T$ Drell-Yan data offer competitive constraints on most new physics scenarios. Furthermore, the full set of correlated constraints from $K$, $\pi$ and $\tau$ decays imposed by $SU(2{)}_L$ gauge invariance is considered. The bounds from $D_{(s)}$ decays, high-$p_T$ lepton tails and $SU(2{)}_L$ relations chart the space of the SMEFT affecting semi(leptonic) charm flavor transitions.

34 pages, 7 figures. v2: Improved discussion in 6.2. Typos corrected. References added. Version submitted to JHEP